Japanese Patent Application Laid-open Publication No. 2010-15516 (hereinafter referred to as PTL1) discloses a data control device of storage system and the like which may reduce risk of data loss. The data control device disclosed in PTL1 sets a difference in frequency of writing data to each of a plurality of nonvolatile semiconductor storage devices, when the device determines that the difference in the frequency of writing data is required.
Japanese Patent Application Laid-open Publication No. 2010-3150 (hereinafter referred to as PTL2) discloses a data management method, a memory controller and the like for flash memories which may extend life of flash memories by reducing the number of rewrites. The memory controller disclosed in PTL2 performs control in a manner to acquire difference data required for rewriting original data already written in a storage device and only to write the differential data to the storage device.
Japanese Patent Application Laid-open Publication No. 2015-60346 discloses a technology relating to a disk array device and the like which may prevent loss of information even when some failure occurs in a Redundant Arrays of Inexpensive Disks (RAID) 0 system having no redundancy.